Retroperitoneal Schwannomas: Dilemmas in Diagnostic Approach and Therapeutic Management

Minimally Invasive Approaches for Lumbosacral Plexus Schwannomas

BACKGROUND AND OBJECTIVES

Lumbosacral plexus schwannomas (LSPSs) are benign, slow-growing tumors that arise from the myelin sheath of the lumbar or sacral plexus nerves. Surgery is the treatment of choice for symptomatic LSPSs. Conventional retroperitoneal or transabdominal approaches provide wide exposure of the lesion but are often associated with complications in the abdominal wall, lumbar or sacral plexus, ureter, and intraperitoneal organs. Advances in technology and minimally invasive (MIS) techniques have provided alternative approaches with reliable efficacy compared with traditional open surgery. We describe 3 MIS approaches using tubular retractor systems according to the lesion level.

METHODS

This was a multicenter, retrospective observational cohort study to evaluate the use of MIS tubular approaches for surgical resection of LSPSs. We included 23 lumbar and upper sacral plexus schwannomas. Clinical presentation, spinal level, surgical duration, degree of resection, days of hospitalization, pathological anatomy of the tumor, approach-related surgical difficulties, and outcomes were collected.

RESULTS

The posterior oblique approach was used in 43.5% of the cases, the transpsoas approach in 39.1%, and the transiliac in 17.4%. The mean operative time was 3.3 hours, and the mean hospitalization was 2.5 days. All tumors were WHO grade 1 schwannoma. Postoperative MRI confirms gross total resection in 91.3% of the patients. No patient requires instrumentation. The pros and cons of each approach were summarized.

CONCLUSION

The MIS approaches adapted to the lumbar level may improve surgeons' comfort allowing a safe resection of retroperitoneal LSPS.

Malignant peripheral nerve sheath tumor with hemophilic syndrome and bone marrow fibrosis: A rare case report

BACKGROUND

Malignant schwannoma is a rare tumor in the peripheral nervous system, accounting for approximately 5% to 10% of systemic soft tissue sarcomas. Especially, malignant schwannoma occurring in the broad ligament of the uterus with hemophilic syndrome and bone marrow fibrosis is extremely rare in clinical practice. Here, we report the first case of an patient diagnosed with malignant peripheral nerve sheath tumor (MPNST) of the broad ligament of the uterus with hemophilic syndrome and bone marrow fibrosis, and share our reference clinical diagnosis and treatment experience.

CASE SUMMARY

A patient was diagnosed with MPNST of the uterus harboring hemophilic syndrome and bone marrow fibrosis. She received combination, and repeated imaging revealed further encountered rare complications (hemophilia syndrome and bone marrow fibrosis) after two cycles of chemotherapy. Thereafter, combined treatment with pazopanib, gemcitabine, and dacarbazine was initiated. Unfortunately, the patient succumbed to death at hospital after two weeks.

CONCLUSION

This report firstly provided reference clinical practice for a patient with MPNST of the uterus harboring hemophilic syndrome and bone marrow fibrosis. Our case raises a reminder about the tolerance and safety of combination therapy, especially in young women.

Integrated Neurosurgical Management of Retroperitoneal Benign Nerve Sheath Tumors

Peripheral nerve sheath tumors (PNST) of the retroperitoneum are rare and are often treated by general surgeons dealing with retroperitoneal cancers. However, resection without the correct microsurgical technique can cause permanent neurological deficits and pain. Here, we discuss our interdisciplinary approach based on the integration of expertise from neurosurgery and abdominal surgery, allowing for both safe exposure and nerve-sparing microsurgical resection of these lesions. We present a series of 15 patients who underwent resection of benign retroperitoneal or pelvic PNST at our institution. The mean age of patients was 48.4 years; 67% were female. Tumors were 14 schwannomas and 1 neurofibroma. Eight patients (53%) reported neurologic symptoms preoperatively. The rate of complete resection was 87% (n = 13); all symptomatic patients showed improvement of their preoperative symptoms. There were no postoperative motor deficits; one patient (7%) developed a permanent sensory deficit. At a mean postoperative follow-up of 31 months, we observed no recurrences. To our best knowledge, this is the second-largest series of benign retroperitoneal PNST consistently managed with microsurgical techniques. Our experience confirms that interdisciplinary management allows for safe treatment of these tumors with good neurological and oncological outcomes.

Clinical characteristics and prognosis of cystic degeneration in retroperitoneal schwannoma: A retrospective study of 79 patients

BACKGROUND AND PURPOSE

Diagnosis of retroperitoneal schwannoma (RS), especially cystic RS, is frequently missed or delayed owing to its rarity, location, nonspecific symptoms, and similarities with other tumors on various imaging modalities. This study aimed to determine associations between clinical, radiological, and histopathologic features and outcome.

MATERIALS AND METHODS

Seventy-nine patients with pathologically confirmed RS who underwent tumor resection between June 2010 and June 2020 were retrospectively reviewed and analyzed. Patients were stratified into three groups according to degree of tumoral cystic degeneration.

RESULTS

Cystic degeneration was significantly associated with multiple foci (p = 0.025), calcification (p = 0.012), and hemorrhage (p = 0.000), but not size (p = 0.08), high Ki-67 (p = 0.094), malignancy (p = 0.115; prevalence of cystic degeneration in the benign and malignant groups were 53.9% vs 100%), rough margin (p = 0.162), or irregular shape (p = 0.369). Malignant RS was significantly associated with multiple lymph nodes enlargement (p = 0.034). Tumor size, margins, shape, or/and multiplicity did not significantly differ between benign and malignant tumors. No recurrence occurred in patients with benign RS (mean follow-up, 45 months). All malignant tumors recurred; mean time to recurrence was 11.4 months (mean follow-up, 33 months).

CONCLUSION

Since RS is misdiagnosed mostly as malignancy and diagnosis is often delayed, a suspicion is necessary for diagnosis when atypical features are present. In RS, cystic degeneration was not associated with tumor size, Ki-67, or malignancy; however, it was significantly associated with multiple foci, calcification, and hemorrhage. Cystic degeneration and related factors are useful for the diagnosis of RS. Malignant RS should be considered when a mass involves multiple lymph nodes. Margins, morphology, and size are not associated with malignancy. Pathological tumor type, tumor location, and adjacent anatomic structures are associated with outcome.

Surgical Principles of Primary Retroperitoneal Sarcoma in the Era of Personalized Treatment: A Review of the Frontline Extended Surgery

Simple Summary

Surgery is the only curative treatment for localized disease in retroperitoneal sarcoma (RPS). Frontline extended surgery, or compartmental surgery, is a recent surgical strategy consisting of resecting the tumor together with adjacent organs, with the aim of minimizing marginality. This review provides a practical step by step description of this standardized procedure, tailored to histologic behavior, tumor localization, and patient condition.

Abstract

Surgery is the key treatment in retroperitoneal sarcoma (RPS), as completeness of resection is the most important prognostic factor related to treatment. Compartmental surgery/frontline extended approach is based on soft-tissue sarcoma surgical principles, and involves resecting adjacent viscera to achieve a wide negative margin. This extended approach is associated with improved local control and survival. This surgery must be tailored to tumor histology, tumor localization, and patient performance status. We herein present a review of compartmental surgery principles, covering the oncological and technical basis, and describing the tailored approach to each tumor subtype and localization in the retroperitoneum.

Extra-Gynecological Pelvic Pathology: A Challenge in the Differential Diagnosis of the Female Pelvis

Ultrasound technology with or without color Doppler allows a real-time evaluation of the entire female pelvis including gynecologic and non-gynecological organs, as well as their pathology. As ultrasound is an accurate tool for gynecological diagnosis and is less invasive and less expensive than other techniques, it should be the first imaging modality used in the evaluation of the female pelvis. We present a miscellany of non-gynecological pelvic images observed during the realization of gynecological ultrasound. Transvaginal and transabdominal ultrasound is the first choice among diagnostic techniques for the study of the female pelvis, providing information about gynecological and extra-gynecological organs, allowing for an orientation toward the pathology of a specific organ or system as well as for additional tests to be performed that are necessary for definitive diagnosis.

Surgical management of ancient retroperitoneal schwannoma

Schwannomas are benign and rare entities of peripheral nerve sheath origin. The clinical presentation depends the size of tumor, and they may cause symptoms of abdominal pain, urinary difficulties, anemia, hematuria, and abdominal mass as a result of the pressure of the tumor to the adjacent structures. The diagnosis can only be established by immunohistochemical study. Complete surgical clearance remains the mainstay of treatment.

We report the case of a 35-year-old female patient consulted for chronic abdominal pain. Abdominal ultrasound and abdomino-pelvic CT scan identified a well-delineated, heterogenous retroperitoneal mass developed in anteraortocaval region measuring 55 × 65 × 88 mm. The lesion seemed to repress the inferior vena cava, and enhanced with contrast administration. The histopathological panel confirmed the diagnosis of retroperitoneal schwannoma.

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Schwannomas are benign and rare entities of peripheral nerve sheath origin.

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They do not lead to an invasion of the adjacent structures; however the compression and displacement of the retroperitoneal organs are marked as complications of increasing in size of these entities.

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The total excision is the sole treatment for retroperitoneal schwannoma.

Robotic Nerve Sheath Tumor Resection With Intraoperative Neuromonitoring: Case Series and Systematic Review

BACKGROUND

Retroperitoneal nerve sheath tumors present a surgical challenge. Despite potential advantages, robotic surgery for these tumors has been limited. Identifying and sparing functional nerve fascicles during resection can be difficult, increasing the risk of neurological morbidity.

OBJECTIVE

To review the literature regarding robotic resection of retroperitoneal nerve sheath tumors and retrospectively analyze our experience with robotic resection of these tumors using a manual electromyographic probe to identify and preserve functional nerve fascicles.

METHODS

We retrospectively analyzed the clinical courses of 3 patients with retroperitoneal tumors treated at the National Institutes of Health by a multidisciplinary team using the da Vinci Xi system. Parent motor nerve fascicles were identified intraoperatively with a bipolar neurostimulation probe inserted through a manual port, permitting tumor resection with motor fascicle preservation.

RESULTS

Two patients with neurofibromatosis type 1 underwent surgery for retroperitoneal neurofibromas located within the iliopsoas muscle, and 1 patient underwent surgery for a pelvic sporadic schwannoma. All tumors were successfully resected, with no complications or postoperative neurological deficits. Preoperative symptoms were improved or resolved in all patients.

CONCLUSION

Resection of retroperitoneal nerve sheath tumors confers an excellent prognosis, although their deep location and proximity to vital structures present unique challenges. Robotic surgery with intraoperative neurostimulation mapping is safe and effective for marginal resection of histologically benign or atypical retroperitoneal nerve sheath tumors, providing excellent visibility, increased dexterity and precision, and reduced risk of neurological morbidity.

Total laparoscopic resection by medial-retroperitoneal approach using virtual navigation: two case reports of primary retroperitoneal schwannoma

Background

We report two rare cases of retroperitoneal schwannoma completely resected by a laparoscopic medial-retroperitoneal approach aided by virtual navigation. Three-dimensional images have been used in liver and lung surgery, but there are few prior reports on retroperitoneal surgery.

Case presentation

These two case reports are of a 60-year-old man and a 40-year-old man with asymptomatic retroperitoneal schwannoma. In both cases, the tumors were located in the right renal hilum and were close to the duodenum, right ureter, and inferior vena cava. Simulation using three-dimensional images was performed before surgery, and a medial-retroperitoneal approach was performed to secure a wide surgical field. During the operation, we confirmed the location of the main feeder and the relationship between the tumor and organs with those shown on the three-dimensional images and performed total laparoscopic resection.

Conclusion

The medial-retroperitoneal approach provides operative safety. Preoperative simulation and intraoperative navigation with three-dimensional images, which can be freely rotated and interactively visualized from any angle, are useful methods to enhance the surgeon’s understanding of a patient’s specific anatomy and are especially effective when resecting a retroperitoneal tumor that is located in an anatomically deep and complex location.

Robotic-assisted excision of a juxta renal retroperitoneal schwannoma

Retroperitoneal schwannoma is a rare benign tumor of the peripheral nerve Schwann sheath. We, herein, report the case of a 74-year-old woman who presented with vague abdominal pain. Computed tomography imaging revealed a retroperitoneal mass that is medial to the right kidney. The patient underwent robotic excision of the tumor with the pathology revealing schwannoma. We report this case due to the scarcity of this disease entity, especially at this location and to emphasize the indication and value of robotic technology in different pathological processes retroperitoneally.

Permanent neurological deficit caused by misdiagnosis of a giant intrapelvic sciatic schwannoma: A case report

Sciatic schwannomas (SSs) are extremely rare, and most are benign. Herein, we report a case of giant SSs in a woman who presented with abdominal pain. Because of the pain pattern and auxiliary examination findings, the patient was initially diagnosed with an ovarian cystadenoma. Magnetic resonance imaging (MRI) revealed an intrapelvic tumor. Histopathological examination confirmed that the mass was a benign intrapelvic schwannoma. Two days after complete tumor resection, the patients experience impaired mobility of the right lower limb. The tumor was 7 × 5.5 × 5 cm³ in size and in contact with the sacrum. The patient was followed up for up to 2 years. No evidence of recurrence was observed in the MRI scan. Severe damages to the sciatic nerve during surgery resulted in permanent neurological deficits. Hence, we also discuss the diagnostic tools and treatments for intrapelvic SSs, as well as the importance of careful radiological examination and multidisciplinary collaboration.

Retroperitoneal Schwannoma: Case report

Schwannoma is a rare benign tumor that comes from the SCHWANN cells that sheath the peripheral nerves. Retroperitoneal location is even rarer than the frequency of this neoplasia. The diagnosis is immuno-histochemical and the treatment is surgical. We report the case of a 36-year-old patient with abdominal pain and transit disorders for 4 months. An abdominal CT scan was found a rounded tissue mass of 10 cm long with well-defined borders. The patient was prepared for surgical removal. Per-operatively, a mass was found in the sub hepatic area, pushing the right kidney backwards. Anatomo-pathological examination was in favor of Schwannoma.

Clinical Characteristics and Treatment Strategy of Retroperitoneal Schwannoma Adjacent to Important Abdominal Vessels: Three Case Reports and Literature Review

Purpose: The purpose of this study was to review the clinical characteristics and treatment strategies of patients with retroperitoneal schwannomas adjacent to important abdominal vessels.

Case Presentation: A total of three patients with retroperitoneal schwannoma immediately adjacent to important blood vessels in the abdominal cavity underwent successful surgical resection. They all had symptoms of abdominal pain and discomfort, two cases underwent three-dimensional reconstruction. There were no serious complications such as peripheral blood vessels and organ damage in all three cases. One case had chyle leakage after surgery, conservative treatment was successfully discharged.

Conclusions: Retroperitoneal schwannomas immediately adjacent to important abdominal vessels have unique clinical characteristics. Preoperative three-dimensional reconstruction can fully show the local vascular relationship of the tumor, which is conducive to surgical planning and risk assessment. Benign tumors with large size and adjacent complex vessels can still be completely resected by surgery. Laparotomy resection is safe and feasible.

Non-functioning retroperitoneal abdominal schwannoma

There are less than 150 cases of non-functioning retroperitoneal abdominal schwannoma (NRS) reported. Hormonal assay is crucial in confirming the diagnosis of NRS, as manipulation of a functional retroperitoneal paraganglioma will instigate an abrupt liberation of catecholamines, resulting in devastating consequences. We report the case of 42-year-old woman who presented with headache, night sweats and abdominal discomfort. Cross-sectional imaging demonstrated a retroperitoneal mass adherent to the aorta and inferior vena cava but biochemical testing of blood and urine was negative for metanephrines and normetanephrines. She underwent successful tumour resection via laparotomy, as location increased the complexity and risk of laparoscopic resection.

Interdisciplinary approach allows minimally invasive, nerve-sparing removal of retroperitoneal peripheral nerve sheath tumors

Purpose

En bloc resection of retroperitoneal peripheral nerve sheath tumors (PNST) is advocated by a variety of surgical disciplines. Yet, microsurgical, nerve-sparing tumor resection might be better suited to improve symptoms and maintain neurological function, especially in cases where patients present with preoperative neurological deficits. However, neurosurgeons, versed in nerve-sparing techniques to remove PNST, are generally unfamiliar with the visceral approaches to retroperitoneal PNST.

Methods

We retrospectively evaluate a series of 16 patients suffering from retroperitoneal PNST. Patients were treated by a unique interdisciplinary approach, combining the visceral surgeon’s skills to navigate the complex anatomy of the retroperitoneal space and the neurosurgeon’s familiarity with microsurgical, nerve-sparing tumor removal. Specifically, we assess whether our interdisciplinary approach is suited to improve preoperative symptoms and maintain neurological function and study whether oncological outcome, surgical morbidity, and operative times are comparable to those reported for “classical” retroperitoneal PNST resection. In addition, we study two cases of suspected PNST that were diagnosed as malignant peripheral nerve sheath tumors (MPNST) after surgery.

Results

Total macroscopic tumor resection was achieved in 14/16 PNST patients. Mean intraoperative blood loss was 680.6 ml (95% CI, 194.3–1167.0 ml) and mean operative time was 162.5 min (95% CI, 121.6–203.4 min). We did not record any major postoperative surgical or neurological complications. A total of 8/11 patients with preoperative pain symptoms reported long-lasting improvement of their symptoms. In terms of oncological outcome, all patients that had been subjected to total tumor removal and for whom follow-up was available, were tumor-free after a mean follow-up of 761.9 days (95% CI, 97.6–1426.0 days). One of the two MPNST patients, who presented with tumor progress 15 months after initial surgery, was subjected to radical re-resection.

Conclusions

Interdisciplinary, nerve-sparing removal of retroperitoneal PNST is well suited to improve preoperative symptoms and maintain neurological function, while achieving an oncological outcome and a surgical morbidity similar to previously reported results for radical retroperitoneal PNST resection. Radical re-resection was feasible in a patient with post hoc MPNST diagnosis.

An interdisciplinary approach for laparoscopic removal of a large retroperitoneal pelvic schwannoma attached to vital vessels: A case report

RATIONALE

Retroperitoneal schwannomas are very rare and may grow very close to major abdominal vessels. Since the surgical approach to the retroperitoneal space may be complex due to surrounding vital organs, including major vessels, laparoscopic surgery is challenging and has only been recently adopted. Here, we report a case of laparoscopic resection of a large retroperitoneal schwannoma attached to large vital vessels.

PATIENT CONCERNS

A 62-year-old woman presented with a chief complaint of pain in the lower right limb with consequent claudication, which had lasted for approximately 1 year.

DIAGNOSES

Magnetic resonance imaging revealed a solid oval mass measuring 45 × 32 × 39 mm, located medially to the right iliopsoas muscle at the level of the intersomatic space between the 5th lumbar vertebra and the 1st sacral vertebra. This mass was inhomogeneously hypointense in T2 due to the presence of cystic areas, with intense and inhomogeneous contrast enhancement, compatible with the diagnosis of a schwannoma. The mass compressed the inferior caval vein near its bifurcation and the right common iliac vein, anteriorly dislocating the ipsilateral iliac arterial axis.

INTERVENTIONS

A multidisciplinary team skilled in vascular and pelvic laparoscopy was involved. The patient underwent laparoscopic surgery via an anterior transperitoneal approach with right adnexectomy and radical excision of the tumor. The surgery lasted 120 minutes without intraoperative complications. Blood loss was less than 100 mL. The histologic diagnosis was a benign Schwannoma; grade I according to World Health Organization classification.

OUTCOMES

The postoperative course was uneventful. At the 10-month follow-up, the patient had no recurrences and was asymptomatic.

LESSONS

Laparoscopic removal of large retroperitoneal schwannomas, even if attached to major vital vessels, is feasible and safe when performed by experienced surgeons.

Intercontinental collaborative experience with abdominal, retroperitoneal and pelvic schwannomas

Background

Schwannomas are rare tumours that pose a significant management challenge in the abdomen, retroperitoneum and pelvis. No data are available to inform management strategy.

Methods

A collaborative international cohort study, across specialist sarcoma units, was conducted to include adults presenting between 2000 and 2017 with histopathologically confirmed schwannomas within the abdomen, retroperitoneum or pelvis.

Results

Of 485 patients across 12 centres, 38 (7·8 per cent) were discharged without follow-up, 199 (41·0 per cent) underwent early resection and 248 (51·1 per cent) had radiological monitoring. Of these 248 patients, 96 (38·7 per cent) eventually had surgery, giving an overall resection rate of 60·8 per cent (295 of 485). At baseline, median tumour volume was 90·1 (i.q.r. 26·5–262·0) cm3. The estimated growth rate was 10·5 (95 per cent c.i. 9·4 to 11·6) per cent per year, and was consistent in the short term (within 2 years of diagnosis) and long term (beyond 2 years) (ρ = 0·405, P = 0·021). A decision to operate was more common in symptomatic patients (P < 0·001) and for rapidly growing tumours (growth rate more than 20 per cent per year) (P = 0·025). R0/R1 resection was achieved in 91·6 per cent of patients (263 of 287). Kaplan–Meier long-term recurrence rates after R0/R1 resection were 2·3 and 6·7 per cent at 3 and 5 years respectively.

Conclusion

Specific recommendations include: indications for early surgery, prediction of growth from radiological monitoring, promotion of selective submacroscopic resection and cessation of postoperative imaging surveillance.

Laparoscopically excised retroperitoneal presacral Schwannoma: atypical pre and postoperative manifestations - case report

BACKGROUND

We are a reporting a rare case of retroperitoneal schwanomma with atypical pre and postoperative manifestations. Retroperitoneal schwannomas are rare tumors that are difficult to preoperatively diagnose.

CASE PRESENTATION

This is a case report of a male patient, 41 years old, with symptoms of hipogastric and lower right member pain, as well as a history of a papilliferous thyroid tumor. Computerized tomography exams were inconclusive, showing a mass in the presacral region with dimensions of 4.4 × 3.9 × 3.4 cm. Removal was carried out by laparoscopic surgery, with self-limited postoperative complications. Diagnosis was carried out by anatomopathological examination, and syndromic hypotheses were discarded.

CONCLUSIONS

The postoperative complications of schwanomma are little reported in the literature. In the simultaneous occurrence of schwanomma and other endocrine tumors, further studies are warranted to better differentiate the cases that need investigation of syndromic causes.

Giant Presacral Schwannoma in Man: Report of a Case with Emphasis on Imaging Findings

BACKGROUND

Schwannoma is a tumor arising from peripheral nerve sheaths and commonly occurs in the head, neck, and upper and lower extremities. Schwannoma in the presacral space is relatively rare and is often misdiagnosed before pathologic diagnosis is made.

CASE DESCRIPTION

Here we discuss a case of giant presacral schwannoma in a 34-year-old man with an emphasis on imaging findings.

CONCLUSIONS

Solid and encapsulated, round or oval, with rich blood supply may be the characteristic imaging findings of presacral schwannoma, which may narrow the differential diagnosis of hypervascular pelvic lesions.

The natural history of incidental retroperitoneal schwannomas

The natural history of asymptomatic retroperitoneal schwannomas is poorly understood. This study aimed at investigating the natural history of incidental retroperitoneal schwannomas. The medical charts and imaging studies of 22 asymptomatic patients under observation for at least 12 months for retroperitoneal schwannomas were reviewed. The duration of follow-up ranged between 13 and 176 months (mean 48 months). In the 22 patients managed by the “wait and see” approach, the average tumor size at initial presentation was 51 mm, which increased to 57 mm at final follow-up. During the final follow-up, 2 patients required surgical treatment for tumor enlargement, while the remaining patients remained asymptomatic without surgery. The average growth rate of the tumors was 1.9 mm/year (range: -1.9 to 8.7 mm/year). The majority of asymptomatic retroperitoneal schwannomas demonstrate minimal growth and may be suitable for management with the “wait and see” approach.

Retroperitoneal space-occupying lesion with displacement of the inferior vena cava

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Exact preoperative diagnosis and surgery of retroperitoneal schwannoma (RS) is sophisticated.

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Due to heterogeneity of the entity, preoperative negative biopsy does not exclude malignancy.

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A curative (R0) resection must be achieved in order to avoid local recurrence, always under consideration of multivisceral resections.

Introduction

The differential diagnosis and therapy of retroperitoneal masses suspicious for soft tissue tumors remains difficult and needs individual decisions as to the best management of patients. We report an unusual case of retroperitoneal schwannoma (RS).

Presentation of case

We report on a 57-year-old female patient with a retroperitoneal space-occupying lesion with displacement, but no infiltration of surrounding vessels, especially the inferior vena cava. As presence of malignancy could not be completely excluded by imaging and biopsy, we performed an open resection of the tumor with plastic reconstruction of the right renal vein. Curative resection of the tumor could be achieved and benign RS verified.

Discussion

Preoperative work-up, including a broad spectrum of differential diagnoses, and consecutive appropriate surgical resection are challenging. Characteristic features of the pre-therapeutic diagnostics of retroperitoneal schwannomas are discussed and differential diagnostic considerations as well as surgical therapeutic options are outlined.

Conclusion

Deeper understanding of retroperitoneal schwannomas gained from preoperative radiologic diagnostics may serve to underline the need for targeted biopsy. This and its histopathological examination necessitate expert interventional radiologists and pathologists. Thus, even the pre-therapeutic diagnostic management should be performed in a specialized center. If doubts remain regarding the entity of the retroperitoneal lesion and findings are still controversial after thorough assessment, surgical oncologic resection represents the therapy of choice, if the surgical risk is adequate.

Large retroperitoneal schwannoma: a rare cause of chronic back pain

Schwannomas are tumours that arise from Schwann cells of the peripheral nerve sheath and rarely occur in the retroperitoneum. We report a 45-year-old woman who presented with a 2-year history of continuous progressive right-sided lower back and dull flank pain radiating into her posterolateral thigh. Abdominal magnetic resonance imaging showed a homogenous soft-tissue tumour with thick capsular lining, which lay in the right retroperitoneum. The tumour was removed at surgery. A histological examination confirmed the diagnosis of benign encapsulated cellular schwannoma. Complete tumour excision should be regarded as the treatment of choice for benign retroperitoneal schwannomas. Successful treatment of these tumours requires thorough preoperative planning and a multidisciplinary approach.

Management of the "Other" retroperitoneal sarcomas

The focus of this review is on the management of the less common sarcomas occurring in the retroperitoneal space, including solitary fibrous tumor (SFT), malignant peripheral nerve sheath tumor (MPNST), perivascular epithelioid cell tumor (PEComa), and undifferentiated pleomorphic sarcoma (UPS) of the psoas muscle. As for other retroperitoneal sarcomas, surgical resection is the mainstay of curative therapy, and multidisciplinary preoperative assessment, including percutaneous needle biopsy for histologic confirmation, is the basis for personalized management, as the surgical management, and the integration of systemic therapy and radiation therapy is unique to each histologic subtype.

Preoperative management of giant retroperitoneal schwannoma: A case report and review of the literature

Schwannomas rarely occur in the retroperitoneum, and are normally not aggressive. Preoperative diagnosis is difficult and the surgeon may confront blood vessels, nerves or organs damage, since the intra-operative findings are various. The diagnosis and treatment of malignant schwannomas in the retroperitoneum are even more challenging. In addition, the prognosis of malignant schwannomas is extremely poor. The present study reports the case of a 52-year-old woman who presented with a 6-month history of an abdominal mass in the left lower quadrant. The local doctor determined a preliminary diagnosis of abdominal giant tumor and referred the patient to the First Affiliated Hospital, Medical School of Xi'an Jiaotong University, (Xi'an, China). Following discussion, the patient underwent a surgical resection. Low-grade malignant schwannoma was diagnosed following histological examination. No evidence of recurrence or any other complication was observed at the 18-month follow-up examination. The present study reports a case of giant retroperitoneal schwannoma (RS), and includes a literature review in order to provide an overview of the diagnosis, treatment and prognosis of RS and discuss preoperative management strategies for the disease.

Lateral access to paravertebral tumors

Traditional transabdominal and retroperitoneal approaches for paravertebral tumors can be associated with injury to the viscera and lumbar plexus. The authors provide a technical description of a known approach with a new application for the resection of paraspinal tumors using both open and minimally invasive transpsoas techniques and report on 2 illustrative cases. In both cases, gross-total resection of the tumor was achieved and the patients experienced resolution of their presenting neurological symptoms, although one of the patients required 2 extra days of hospitalization due to an asymptomatic retroperitoneal hematoma, which was conservatively managed.

The authors conclude that the lateral transpsoas approach is a safe approach for paravertebral tumors and may not require an access surgeon.

A minimally invasive pericoccygeal approach to resection of a large presacral schwannoma: case report

Resection of large presacral schwannomas can present a challenge. The posterior approach is commonly associated with coccygeal disarticulation, partial sacral resection, and muscular disarticulation, which can all result in significant morbidity. Minimally invasive surgery may obviate some of the morbidity traditionally associated with this approach. The authors present the case of a morbidly obese 49-year-old man with an enlarging presacral schwannoma. The patient refused laparoscopic resection because of the morbidity he had experienced with a previous laparoscopic surgery. The tumor was resected using a minimally invasive paracoccygeal approach, which affords improved access with minimal morbidity.

Retroperitoneal schwannomas: advantages of laparoscopic resection. Review of the literature and case presentation of a large paracaval benign schwannoma (with video)

Retroperitoneal schwannomas represent 0.5%-3% of all retroperitoneal tumors. Complete surgical removal is the treatment of choice because it permits a correct histological diagnosis and prevents eventual degeneration. Laparoscopic surgery has been reported as safe and effective by several authors. We present a comprehensive review of the literature regarding the role of laparoscopy in surgical resection of retroperitoneal schwannomas, and we present a case showing the technique (with video). Laparoscopic resection in experienced hands is safe and effective, and guarantees excellent postoperative results in terms of patient recovery.